Erasing flash when there is a BLE Connection

[Gordon]

Hi! I'm running the Espruino JavaScript interpreter on a Nordic nRF51 (actually the BBC micro:bit), and I am finding it will totally reset itself when trying to erase a page of flash memory while also connected to BLE

BLE is enabled by default, and erasing the page works (via nrf_nvmc_page_erase(addr);) just fine normally (while the device is advertising). However if I connect to the Nordic UART service, and then execute the exact same code in the exact same way, the chip just resets.

Do you have any ideas what could be causing this or how to fix it?

thanks!

[Susheel Nuguru]

Seems like there is some error returned in one of the functions in your code. You know that APP_ERROR_CHECK default behavior is that it if the condition inside it does not pass, then it will reset you chip. Try to look at this thread. First try to find exact place where the system resets.

[Gordon]

Ahh, thanks! I'd got a ble_app_error_handler but not a app_error_fault_handler. Adding that definitely changes the behaviour, but it isn't able to print anything - which makes me think it is being called from within an IRQ (which would be something to do with BLE, since at that point I don't have any active IRQs).

Any idea what could actually be causing this, or how it could be avoided? Unfortunately I don't have debugging set up. Presumably the BLE stack interrupts in the middle of a flash write, and doesn't like it for some reason?

[Susheel Nuguru]

Accessing flash directly while BLE activity is not safe and might lead to flash corruptions and softdevice assertions.

You can use sd_flash_page_erase API that synchronizes with softdevice and makes sure that it is not interrupted by BLE activity.

[Gordon]

Perfect, thanks! That'll almost certainly be the problem then - I was using nrf_nvmc_page_erase

[Gordon]

edit: solved.